C# – 在Listbox中保存值

SaveFileDialog saveGC1File = new SaveFileDialog();

private void GCSavePlacementOneButton_Click(object sender,EventArgs e)
{
    // Initialize the SaveFileDialog to specify the .txt extension for the file.
    saveGC1File.DefaultExt = "*.txt";
    saveGC1File.Filter = ".txt Files|*.txt|All Files (*.*)|*.*";
    saveGC1File.RestoreDirectory = true;

    try
    {
        string placementOneSave = placementOneListBox.Items.ToString();

        // Save the contents of the formattedTextRichTextBox into the file.
        if (saveGC1File.ShowDialog() == DialogResult.OK && saveGC1File.FileName.Length > 0)
            placementOneSave.SaveFile(saveGC1File.FileName,RichTextBoxStreamType.PlainText);

        // Throws a FileNotFoundException otherwise.
        else
            throw new FileNotFoundException();
    }

    // Catches an exception if the file was not saved.
    catch (Exception)
    {
        MessageBox.Show("There was not a specified file path.","Path Not Found Error",MessageBoxButtons.OK,MessageBoxIcon.Warning);
    }
}

但是,使用Visual Studio 2010,“if”循环中的行指出：

"placementOneSave.SaveFile(saveGC1File.FileName,RichTextBoxStreamType.PlainText);"

在“SaveFile”下面有一个红线..我之前使用过这段代码保存文件,不确定为什么它不能用于ListBox.

质询

>如何以类似于RichTextBox的方式保存ListBox？
>任何编辑此代码的方法都可以让用户选择ListBox的保存位置？